const state = {
	visitedViews: [],
	cachedViews: []
};

const mutations = {
	ADD_VISITED_VIEW: (state, view) => {
		if (state.visitedViews.some(v => v.path === view.path)) {
			return;
		}
		state.visitedViews.push(
			Object.assign({}, view, {
				title: view.meta.title || 'no-name'
			})
		);
	},
	ADD_CACHED_VIEW: (state, view) => {
		if (state.cachedViews.includes(view.name)) {
			return;
		}
		if (!view.meta.noCache) {
			state.cachedViews.push(view.name);
		}
	},

	DEL_VISITED_VIEW: (state, view) => {
		for (const [i, v] of state.visitedViews.entries()) {
			if (v.path === view.path) {
				state.visitedViews.splice(i, 1);
				break;
			}
		}
	},
	DEL_CACHED_VIEW: (state, view) => {
		const index = state.cachedViews.indexOf(view.name);
		index > -1 && state.cachedViews.splice(index, 1);
	},

	DEL_OTHERS_VISITED_VIEWS: (state, view) => {
		state.visitedViews = state.visitedViews.filter(v => {
			return v.meta.affix || v.path === view.path;
		});
	},
	DEL_OTHERS_CACHED_VIEWS: (state, view) => {
		const index = state.cachedViews.indexOf(view.name);
		if (index > -1) {
			state.cachedViews = state.cachedViews.slice(index, index + 1);
		} else {
			// if index = -1, there is no cached tags
			state.cachedViews = [];
		}
	},

	DEL_ALL_VISITED_VIEWS: state => {
		// keep affix tags
		state.visitedViews = state.visitedViews.filter(tag => tag.meta.affix);
	},
	DEL_ALL_CACHED_VIEWS: state => {
		state.cachedViews = [];
	},

	UPDATE_VISITED_VIEW: (state, view) => {
		for (let v of state.visitedViews) {
			if (v.path === view.path) {
				v = Object.assign(v, view);
				break;
			}
		}
	}
};

const actions = {
	addView({ dispatch }, view) {
		dispatch('addVisitedView', view);
		dispatch('addCachedView', view);
	},
	addVisitedView({ commit }, view) {
		commit('ADD_VISITED_VIEW', view);
	},
	addCachedView({ commit }, view) {
		commit('ADD_CACHED_VIEW', view);
	},

	delView({ dispatch, state }, view) {
		return new Promise(resolve => {
			dispatch('delVisitedView', view);
			dispatch('delCachedView', view);
			resolve({
				visitedViews: [...state.visitedViews],
				cachedViews: [...state.cachedViews]
			});
		});
	},
	delVisitedView({ commit, state }, view) {
		return new Promise(resolve => {
			commit('DEL_VISITED_VIEW', view);
			resolve([...state.visitedViews]);
		});
	},
	delCachedView({ commit, state }, view) {
		return new Promise(resolve => {
			commit('DEL_CACHED_VIEW', view);
			resolve([...state.cachedViews]);
		});
	},

	delOthersViews({ dispatch, state }, view) {
		return new Promise(resolve => {
			dispatch('delOthersVisitedViews', view);
			dispatch('delOthersCachedViews', view);
			resolve({
				visitedViews: [...state.visitedViews],
				cachedViews: [...state.cachedViews]
			});
		});
	},
	delOthersVisitedViews({ commit, state }, view) {
		return new Promise(resolve => {
			commit('DEL_OTHERS_VISITED_VIEWS', view);
			resolve([...state.visitedViews]);
		});
	},
	delOthersCachedViews({ commit, state }, view) {
		return new Promise(resolve => {
			commit('DEL_OTHERS_CACHED_VIEWS', view);
			resolve([...state.cachedViews]);
		});
	},

	delAllViews({ dispatch, state }, view) {
		return new Promise(resolve => {
			dispatch('delAllVisitedViews', view);
			dispatch('delAllCachedViews', view);
			resolve({
				visitedViews: [...state.visitedViews],
				cachedViews: [...state.cachedViews]
			});
		});
	},
	delAllVisitedViews({ commit, state }) {
		return new Promise(resolve => {
			commit('DEL_ALL_VISITED_VIEWS');
			resolve([...state.visitedViews]);
		});
	},
	delAllCachedViews({ commit, state }) {
		return new Promise(resolve => {
			commit('DEL_ALL_CACHED_VIEWS');
			resolve([...state.cachedViews]);
		});
	},

	updateVisitedView({ commit }, view) {
		commit('UPDATE_VISITED_VIEW', view);
	}
};

export default {
	namespaced: true,
	state,
	mutations,
	actions
};
